# Inverse function

From ACT Wiki

1.

A mathematical function which reverses another function.

For example the square root function x^{(1/2)} is the inverse function of the square function x^{2}.

Another example is the Natural logarithm (log to the base 'e') which is the inverse function of the exponential function e^{x}.

2.

The function 1/x, also written x^{-1}.

(As it happens, the inverse function of 1/x - in the first sense above - is itself, namely 1/x.)